BOP (benzotriazol-1-yloxytris(dimethylamino)phosphonium hexafluorophosphate) is a reagent commonly used for the synthesis of amides from carboxylic acids and amines in peptide synthesis.

[3] This reagent has advantages in peptide synthesis since it avoids side reactions like the dehydration of asparagine or glutamine redisues.

[4] BOP has used for the synthesis of esters from the carboxylic acids and alcohols.

[5] BOP has also been used in the reduction of carboxylic acids to primary alcohols with sodium borohydride (NaBH4).

[6] Its use raises safety concerns since the carcinogenic compound HMPA is produced as a stoichiometric by-product.